Method of packaging fragile articles

ABSTRACT

A METHOD OF PACKAGING FRAGILE ARTICLES WHICH INCLUDES ENCLOSING THE ARTICLE IN AN IMPERVIOUS ENVELOPE WITH THE ENVELOPE IN CONTIGUOUS RELATION TO THE SURFACE CONTOUR OF THE ARTICLE, AND SPRAYING THE OUTER SURFACE OF THE ENVELOPE WITH A LIQUID REACTION MIXTURE WHICH FORMS IN SITU A CELLULAR ENERGY ABSORBING CUSHION AROUND THE ARTICLE.

Jan. 26, 1971 v F, UR 3,557,518

' METHOD OF PACKAGING. FRAGILE ARTICLE;

FIG, 4

Filed June 5 1968 /NVN70,Q 5 Fred 5 P 5, r y

3,557,518 7 METHOD OF PACKAGING FRAGILE ARTICLES Fred B. Purkey, Morristown, Tenn., assignor to The Berk-,

line Corporation, Morristown, Tenn., a corporation of Tennessee Filed June 5, 1968, Ser. No. 734,656 Int. Cl. B65b 41/18 US. C]. 5327 Claims ABSTRACT OF THE DISCLOSURE A method of packaging fragile articles which includes enclosing the article in an impervious envelope with the envelope in contiguous relation to the surface contour of the article, and spraying the outer surface of the envelope with a liquid reaction mixture which forms in situ a cellular energy absorbing cushion around the article.

This invention relates to a method of packagingitms in rigid cushioning foam and to the package produced by said method.

Heretofore, articles of furniture and the like have been prepared for shipment by packaging them in corrugated containers or crates which are sized to accommodate the largest dimensions of the article being packaged, so that when such packages are positioned within a van or other transport vehicle, a large portion of the available capacity of the vehicle is lost by virtue of the dead space in each of the packages. Such packages are, of course, costly to fabricate.

In some instances, articles of furniture, such as upholstered pieces, are shipped in vans and are merely covered by quilted pads which afiord inadequate protection to the article and, further, sometimes soil the articles with which they come in contact because the pads themselves become soiled as a result of continued use.

In accordance with my invention, I provide a method of packaging articles, for example, furniture and the like, which comprises positioning the article to be packaged within an envelope of suitable impervious material, for example, polyethylene, sheet paper, or the like, the envelope being sealed to prevent the ingress of any foreign material into the interior thereof and being contiguous to the contours of the article. The article is then sprayed With a polymeric-isocyanate mix which reacts to form a rigid or cushioning polyurethane foam, completely encapsulating the article like a cocoon or shell 15, or the foam may be applied to selected portions of the article, in the manner of a frame, to aiford desired protection only to certain portions of the article, as desired. The foam, in either case, may be applied in any desired thickness and the frame or cocoon serves as the shipping container for the article.

In the accompanying drawings:

FIG. 1 is a more or less diagrammatic elevational view, illustrating the step of evacuating the envelope enclosing the article so as to obtain a contiguous or form-fit relation between the envelope and the article.

FIG. 2 illustrates the application of the foam to the outer surface of the envelope.

FIG. 3 is a vertical cross-sectional view showing the article of furniture completely encapsulating in a foam cocoon, and

FIG. 4 is a cross-sectional view on an enlarged scale taken substantially on line 4-4 of FIG. 3.

Referring to the drawings, the numeral indicates an article of furniture, in the form of a chair, which is enclosed in an envelope 11 of suitable sheet plastic, for example, polyethylene, or paper, or as an alternative the envelope may consist of a flexible strippable coating applied, as by spraying, to the surface of the article.

3,557,518 Patented Jan. 26, 1971 lice In the case of a loosely fitting envelope the interior of the same is evacuated, as with a hose 12 connected to a' suitable vacuum pump so as to effect intimate or contiguous engagement of the envelope with the contours of the article. In other Words, the envelope is form-fitting in relation to the outer surfaces of the article, as illustrated in FIG. 2. In the case of an envelope which may be heat-shrinkable, it will be understood that it will be required to pass such an envelope enclosing the article under a heat source to effect shrinkage of the envelope to a form-fit. A sheet of corrugated paper cardboard I or any suitable material, not shown, may be placed under the article, for example, under the legs of the chair,

so as to facilitate enclosure of the article or to give the packaged article a more desired appearance.

As illustrated in FIG. 2, a rip cord 13 is laid over or around the back and seat of the chair on top of the envelope for the purpose of facilitating removal of the rigid foam subsequently to be applied.

.The enclosed article is now in condition to receive the application of a liquid foamable rigid or flexible cushioning foam reaction mixture which is applied as with a spray gun of a well-known type. A rigid or cushioning solid cellular foam forms in situ. The foam may be applied on all surfaces of the envelope to fully enclose the article to a desired thickness, as illustrated in FIG. 3, in the nature of a cocoon. The thickness of the cellular foam may be varied to provide a desired degree of protection and strength by spraying on several applications of the material, or the spray gun may be adjusted to deliver the desired quantity of material in one operation.

It will be understood that in certain situations it may not be necessary to completely enclose the article and, accordingly, only the areas desired to be protected are sprayed to obtain a desired thickness of foam. This might be in the nature of a frame of foam surrounding the article and protecting certain areas against injury. It will also be understood that where a cocoon-type of enclosure is desired the thicknesses of the foam around the article may be varied, depending upon the degree of protection desired in any particular area. Because the envelope is form-fitting and contiguous to the surface contours of the article, the foam itself is supported by the article.

An important advantage of the above described invention is that the package assumes the general shape and configuration of the article enclosed and, accordingly, this permits the loading or stacking of articles in a van or box-car in a more compact arrangement than is possible when such aritcles are packaged in conventional type cartons.

Polyurethane foam has excellent energy absorbing characteristics to protect the article against shock or impact. Further, the foam has highly desirable thermal insulation properties and high resistance to deterioration, vermin, insects and fungi and, additionally, may also be made flame-retardant.

The polyurethane shell 15 affords protection to the article both while in transit and in storage. In order to remove the shell it is merely required to pull the rip cord 13 to effect fracture of the shell and then remove the shell from around the article.

The polyurethane foam used in forming my package may be rigid or flexible, preferably having a density of one to three pounds per cubic foot. However, the density may range from one to fifty pounds per cubic foot. A rigid polyurethane foam may be produced through the use of a pre-polymer and catalyst system identified in the trade as Isofoam D-2444, manufactured by Isocyanate Products, Inc. of Newcastle, Delaware. A suitable foam may be prepared by mixing parts of pre-polymer containing 27.5% of free NCO (isocyanate) groups with a resin containing a polyol, refrigerant 11 and a H suitable catalyst well-known in urethane technology. A flexible foam may be obtained through the use of Isofoam L6, also a product of this compa ny. It will also be understood that other types of foam formed of polystyrene, phenolic or polyethylene foam mixtures may be utilized for spray-on applications, if they are formulated to produce rigid or flexible foams within the desired density range.

Any suitable equipment for spraying two component plastic coatings and foam systems may be employed. For example, one such apparatus is manufactured by Gusmer Coatings, Inc. of Woodbridge, N.J., and includes a model B spray gun and model FF proportioner. This equipment is particularly designed for spray-in-place polyurethane foam.

It will be understood that various changes and modifications may be made from the foregoing without departing from the spirit and scope of the appended claims.

What is claimed is:

1. The method of packaging a fragile article comprising enveloping said article in an impervious envelope, evacuating said envelope to effect contiguity of said en- 4 velope to th e contoursof said article, spraying the surface of said envelope with a liquid reaction mixture which forms a cellular energy absorbing cushion on said envelope having substantial thickness and which assumes the general configuration of the article itself.

2. The invention as defined in claim 1 in which the cushion is readily rupturable.

3. The invention as defined in claim 1 in which the cushion is polyurethane.

4. The invention as defined in claim 1 in which the density of the cushion is from one to thirty pounds per cubic foot.

5. The invention as defined in claim 1 in which substantially the entire article is enclosed by said cushion.

References Cited UNITED STATES PATENTS 2,020,255 11/ 1935 Copeman 5327X 3,039,245 6/1962 Jones 5327X 3,204,385 I 9/1965 De Remer et al. 5327 3,429,095 2/ 1969 I-Iuson 53-27X H. A. KILBY, In, Primary Examiner 

